PLEASE HELP ME I DONT UNDERSTAND MY HOMEWORK AND ITS TUE TODAY

Answer:
All of the above
Step-by-step explanation:
The question is asking you which equation you can use for you to find the value of the undefined variable, n.
In this case, all of the equations above are eligible to find the value of the variable n since regardless of the variable position, you will yet be able to find its value.
Answer:
n- 15 = 4 is the answer.
hope this is helpful ^_^